Perovskite-TOPCon Tandem Solar Cells & PD-5000C Sputtering System

In the global photovoltaic industry’s pursuit of lower Levelized Cost of Energy (LCOE), the efficiency of traditional crystalline silicon solar cells is approaching its theoretical limit. As a next-generation solution, perovskite-TOPCon tandem solar cells are emerging as one of the most promising technologies for ultra-high-efficiency photovoltaics.

Compared with the theoretical efficiency limit of approximately 29.4% for single-junction TOPCon solar cells, tandem perovskite structures can potentially reach 45–46%. Single-junction perovskite cells already demonstrate a theoretical limit of around 31%, and certified tandem devices have achieved conversion efficiencies of 34.22%, with open-circuit voltage exceeding 2.01V.

Efficiency Breakthrough Through Spectral Utilization

The core principle of perovskite-TOPCon tandem solar cells is spectral complementarity. A wide-bandgap perovskite top cell absorbs high-energy photons, while a narrow-bandgap silicon bottom cell captures lower-energy light.

These two sub-cells are connected through a tunnel recombination junction, enabling efficient charge transfer and minimizing energy loss. This stacked architecture significantly reduces thermalization losses, enabling higher overall energy conversion efficiency compared to single-junction silicon cells.

Simplified Manufacturing Process and Application Potential

Perovskite solar technology offers a simpler and lower-energy manufacturing route compared to conventional crystalline silicon production. Traditional silicon solar cell fabrication typically involves more than 15 high-temperature steps, while perovskite devices can be produced through approximately 5–10 low-temperature solution or printing processes.

This reduction in process complexity leads to lower equipment investment, reduced energy consumption, and faster production cycles. In addition, perovskite materials enable flexible, semi-transparent, and even colored solar modules, expanding application scenarios such as building-integrated photovoltaics (BIPV), automotive surfaces, and portable energy systems. However, industrialization still faces challenges, including moisture sensitivity, ion migration, long-term thermal stability, and environmental concerns related to lead management.

Key Thin-Film Deposition Process

The fabrication of perovskite-TOPCon tandem solar cells includes several critical steps: substrate cleaning, transparent conductive electrode deposition, electron transport layer (ETL) formation, perovskite absorber deposition, and hole transport layer (HTL) deposition.

Among these, the quality of transparent conductive oxide (TCO) layers such as ITO and functional oxide films plays a decisive role in device efficiency and long-term stability. This makes advanced sputtering equipment essential for high-performance production.

PD-5000C Large-Area Magnetron Sputtering System

To support advanced photovoltaic manufacturing, ChinTiyan developed the PD-5000C large-area continuous magnetron sputtering coating system.

This equipment is designed for high-precision thin-film deposition of metal layers (Ti, Cu, Ni), dielectric films, and oxide coatings such as ITO and NiO.

Key technical capabilities include:

• Maximum substrate size: 600mm × 600mm 
• Multi-chamber system: 3–5 vacuum chambers 
• Ultimate vacuum level: 2.0 × 10⁻⁵ Pa 
• Substrate heating: up to 300°C+ with ±1°C control accuracy 
• Temperature uniformity: ±3%–5% 
• Sputtering targets: 2–4 units (800 × 120 × 7 mm) 

These parameters ensure a stable, ultra-clean deposition environment for high-quality thin films used in tandem solar cells.

High-Throughput Design and Film Quality Enhancement

The PD-5000C system is equipped with an efficient loading and unloading trolley mechanism, significantly improving production cycle efficiency.

Its dual-track transport system ensures stable movement between chambers, even under high-temperature vacuum conditions, improving process repeatability and yield consistency.

In addition, the substrate holder integrates a bias voltage design, which enhances film density and adhesion strength. This is critical for improving interface quality and long-term stability in perovskite-TOPCon tandem solar cells.

Conclusion

Perovskite-TOPCon tandem solar technology represents a major breakthrough in photovoltaic efficiency and next-generation solar development.

At the same time, it places higher demands on precision manufacturing equipment. With advanced vacuum control, thermal stability, and continuous deposition capabilities, the PD-5000C sputtering system developed by ChinTiyan provides a reliable solution for scaling up tandem solar cell production from laboratory research to industrial manufacturing.